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Black tank valve

freewayrandy
Explorer
Explorer
We are on the road and my friend dumped his black tank, closed the valve and flushed then went to open the valve and it barely opened. Pulled and pulled and it would not open all the way. What could be wrong?
2022 Chevy Silverado 2500 HD Duramax/Allison, 2024 Cougar 27SGS
4 REPLIES 4

ReneeG
Explorer
Explorer
What happened to the OP? I'd like to know what became of their problem with the valve.
2011 Bighorn 3055RL
2011 F350 DRW 6.7L 4x4 Diesel Lariat and Hensley TrailerSaver BD3
1992 Jeep ZJ and 1978 Coleman Concord Pop-Up for remote camping
Dave & Renee plus (Champ, Molly, Paris, Missy, and Maggie in spirit), Mica and Mabel, both Rat Terriers!

ReneeG
Explorer
Explorer
First thing to try, and I speak from experience, is to put Thetford Drain Valve Lubricant in your tank. Our valve was stuck open which is the opposite of yours. It's better and recommended to treat the valve with it closed. So at the advice of the local RV supply and shop, we bought the Thetford, ran hot water in our toilet (using buckets), managed to get the valve closed, which is what you want. We let it sit (preferred to drive around so the liquid swishes around), but for us it worked. We can open and close easily now. I put additional treatment in along with two gallons of hot water. Why they stick can be because sludge builds up around it much like the valve on your lawn mower when you move between mulch and bag. Try that first before you panic and have to take things apart.
2011 Bighorn 3055RL
2011 F350 DRW 6.7L 4x4 Diesel Lariat and Hensley TrailerSaver BD3
1992 Jeep ZJ and 1978 Coleman Concord Pop-Up for remote camping
Dave & Renee plus (Champ, Molly, Paris, Missy, and Maggie in spirit), Mica and Mabel, both Rat Terriers!

opnspaces
Traveler II
Traveler II
wait until evening and hook it up at the dump station and let it trickle until drained. Then you can disconnect the valve and see what's going on.
.
2001 Suburban 4x4. 6.0L, 4.10 3/4 ton **** 2005 Jayco Jay Flight 27BH **** 1986 Coleman Columbia Popup

WILDEBILL308
Explorer
Explorer
Most likely jammed up with paper. As long as he drained it he can take it off and clean/lube it or replace it.
Bill
2008 Newmar Mountain Aire
450 HP CUMMINS ISM
ALLISON 4000 MH TRANSMISSION
TOWING 2014 HONDA CRV With Blue Ox tow bar
A man who carries a cat by the tail learns something he can learn in no other way.
-Mark Twain